The invention relates to a robotic camera dolly system, and more specifically to such a system which can remotely and automatically direct a camera dolly among studio floor positions.
As the television broadcast market continues to mature, there is growing interest in controlling costs and improving equipment utilization through the greater use of automation. Newsrooms are leading the way. Central computers are being used to organize the overall news gathering process and the sequencing of the show, and increasingly to control certain studio equipment such as teleprompters.
The trend is toward controlling ever more studio equipment, such as lighting, character-generators, and effects generators.
Cameras, however, are still manually controlled despite the fact most of their shots are well structured, highly repetitive, and known in advance. Automating them therefore has the potential to further reduce costs and improve equipment utilization in an automated studio. Automating shot taking would require that the shots be framed before the television show, assigned names, and then recalled as needed.
A camera shot can be thought of as consisting of seven parameters, all set by the cameraman. They are camera focus, zoom, tilt, pan, pedestal height, and the x and y positions of the camera dolly on the floor. Ideally all seven degrees of freedom are servo controlled, and stored as a set. The control and storage of the first four parameters: focus, zoom, tilt, and pan, is known within the prior art. Examples are the products manufactured by Total Spectrum Manufacturing Inc., known as the Multicontroller and the HS-110-P robotic camera head. Partial camera automation is practical at this level, but the cameras must either be anchored, or dollied about manually. These restrictions tend to nullify the gains of automation, obtainable with respect to focus, zoom, tilt, and pan, since the restrictions require manual intervention, or additional cameras, or aesthetic compromises.
One way to achieve mobility is to place the cameras on a track; however this method has its drawbacks. It clutters the floor, is expensive to relocate, is one-dimensional, limits camera locations to those along the track, and prevents the cameras from crossing past each other.
Another way to achieve mobility is to place the cameras on wheeled dollies and, with the aid of a motor control system, to direct the dollies to the appropriate camera locations and angular orientations. However, this approach runs into the problem of assuring precision in movements which may be of the order of 50 feet in a typical television studio, it being obviously very important in television production that both the location and orientation of the cameras be properly located while shooting. Moreover, when a series of predetermined locations is to be traversed by the camera the problem would become successively magnified as such error would accumulate from shooting location to shooting location.